1. Field of Invention
The present invention is in the field of olefin oligomerization. More specifically, the present invention relates to oligomerization of olefins in the liquid phase with a catalyst comprising the combination of a nickel-containing silicaceous crystalline molecular sieve and a hydrocarbyl aluminum halide.
2. Description of the Prior Art
Non-zeolitic catalyst combinations using hydrocarbyl aluminum halides for oligomerizing olefins are known in the art. For example, U.S. Pat. Nos. 4,366,083 and 4,283,305 disclose catalyst compositions for oligomerizing olefins obtained by contacting a hydrocarbyl aluminum halide and a nickel carboxylate.
U.S. Pat. No. 3,622,469 discloses a catalyst system comprising NiCl.sub.2, triisopropylphosphine and an hydrocarbyl aluminum halide to convert propylene to a mixture of C.sub.6 olefins.
Oligomerization and polymerization of olefins in the gas phase over various zeolites is also known in the art. For example, U.S. Pat. No. 3,960,978 a process for producing a gasoline fraction containing predominantly olefinic compounds which comprises contacting a C.sub.2 to C.sub.5 olefin with a ZSM-5 type crystalline aluminosilicate zeolite at a temperature of from about 500.degree. F. to about 900.degree. F. is disclosed.
U.S. Pat. No. 4,021,502 describes the conversion of gaseous C.sub.2 to C.sub.5 olefins into gasoline blending stock by passage over ZSM-12 at temperatures of from about 400.degree. F. to about 1200.degree. F.
U.S. Pat. No. 4,254,295 discloses a process for the oligomerization of olefins by contacting said olefins in the liquid phase with ZSM-12 catalyst at temperatures of 80.degree. F. to 400.degree. F.
In copending application U.S. Ser. Nos. 584,031 and 584,078, both filed on Feb. 27, 1984, of common inventive entity processes are disclosed for oligomerizing C.sub.2 -C.sub.20 olefins by contacting said olefins in the liquid phase with a nickel-containing silicaceous crystalline molecular sieve catalyst.
It has now been found that the activity of the nickel-containing silicaceous crystalline molecular sieve catalyst described in the above-mentioned co-pending applications, for oligomerizing C.sub.2 to C.sub.20 olefins may be increased by combining the catalysts with a hydrocarbyl aluminum halide.